An inkjet head used for an inkjet printer includes a base substrate, piezoelectric elements placed on the base substrate and engraved with channel grooves, a frame member placed on the base substrate to surround the piezoelectric elements, and a nozzle plate bonded to the upper ends of sidewalls of the channel grooves of the piezoelectric elements by an adhesive and having nozzle holes.
The inkjet head sucks ink into the inside of the channel grooves according to deformation of the piezoelectric elements in one direction and ejects the ink in the inside of the channel grooves from the nozzle holes according to deformation of the piezoelectric elements in another direction.
In the inkjet head in the past, if the adhesive is excessively applied to the upper ends of the sidewalls of the channel grooves of the piezoelectric elements, a large amount of the adhesive is extruded into the inside of the channel grooves serving as pressure chambers. If the adhesive is extruded more than expected, the capacity of the pressure chambers decreases and a specified amount of the ink cannot be ejected and ink arrival accuracy substantially falls.
The nozzle holes are drilled after the nozzle plate is bonded to the piezoelectric elements. If the adhesive reaches drilling positions of the nozzle holes, the nozzle holes are drilled in a deformed shape rather than a circular shape. When a nozzle plate having nozzle holes drilled therein in advance is bonded to the piezoelectric elements, if the adhesive reaches drilling positions of the nozzle holes, the nozzle holes are deformed without keeping a circular shape. If the nozzle holes are deformed, printing quality is adversely affected.